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arXiv · 1712.01513

Circular dichroism of chiral Majoranas

Javier Osca·Llorenç Serra
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Abstract

Majorana states in condensed matter devices may be of a localized nature, such as in hybrid semiconductor/superconductor nanowires, or chirally propagating along the edges such as in hybrid 2D quantum-anomalous-Hall/superconductor structures. We calculate the circular dichroism due to chiral Majorana states in a hybrid structure made of a quantum-anomalous-Hall-insulator and a superconductor. The optical absorption of chiral Majoranas is characterized by equally spaced absorption peaks of both positive and negative dichroism. In the limit of a very long structure (a 2D ribbon) peaks of a single sign are favored. Circular-dichroism spectroscopy of chiral Majoranas is suggested as a relevant probe for these peculiar states of topological matter.

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Javier Osca, Llorenç Serra. 2017-12-13. Circular dichroism of chiral Majoranas. https://doi.org/10.3762/bjnano.9.110

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